A bulbous bow is used on sea-going vessels in order to enable a better hydrodynamic engagement with the water, lowering the overall resistance of the vessel when traveling through said water. The bulbous bow design has been around for decades, and is a very widely used and recognized solution for breaking the water in an optimal way for larger vessels, lowering the overall resistance of said vessel, allowing for a smaller propulsion system, thereby reducing the consumption of fuel.
In FR2822797A1 there is disclosed a solution for collisions and other types of damage to a bulbous bow, by designing a bulbous bow with a spring mechanism inside to absorb any damage to the bow coming from the front of the bow, and enabling the whole bulbous bow to detach from the hull of the vessel. The design is very simple and straight forward, but raises manufacturing costs rather than lowering them, by making the bulbous bow more complex, while maintaining the double curved surfaces in the design. The detachable and replaceable bulbous bow is a heavy and complicated procedure, and will still be costly.
JP2015517951A discloses a manufacturing and attachment method for manufacturing a bulbous bow in a high strength weldable material, such as steel, and welding it onto a hull, as well as a subsequent inspection of the weldings. This is a new take on the traditional way of manufacturing and attaching bulbous bows to hulls, and describes the difficulty and problems of welding and checking the tightness of the assembly.
U.S. Pat. No. 4,323,026A describes a fluid based collision dampening design of a bulbous bow. The bulbous bow is filled with a fluid, which when the bow collides with another object, will minimize the damage to the hull of the vessel by draining the fluid of the bulbous bow into a cavity in a controlled manner. This minimizes damage to the main hull of the vessel as well as the damage to whatever is collided with, but does not lower the manufacturing costs of the bulbous bow, on the contrary the solution adds complexity to the construction, adding manufacturing costs.
WO2004092004A1 describes a bow of a vessel designed to bend away in case of collision, minimizing damage to the vessel as well as whatever it collides with. The bow is manufactured in the traditional manner, double curved steel plates and underlying structure, making the design more expensive as it adds complexity.
Traditionally the bulbous bow is manufactured in metal which is cut and hammered out into double curved surfaces, which is a very difficult and expensive process.